Just like oxalates, polyphenols in foods are usually considered very healthy, but unless you have microbes that utilize specific polyphenols, you may not get full benefit from them. One example is a substance found in these foods called ellagic acid. We can detect if your microbiome is metabolizing ellagic acid and converting it into urolithin A.. It is only the urolithin A that has anti-inflammatory and antioxidant effects. Without the microbes to do this conversion you will not benefit from ellagic acid in foods.
Examples; Walnuts, raspberries, pomegranate, blackberries, pecans, and cranberries all contain ellagic acid.
We have analyzed tens of thousands of people, and only about 50% of the people actually benefit from eating more foods containing ellagic acid.
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